Door with a weight-balancing device with helical springs

ABSTRACT

An overhead garage door arrangement in which a door leaf is moveable between open and closed position, and is installable against a ceiling for sliding up and down or that can be tilted or swung up and down for compensating against the weight of the door, at least one helical spring module is provided with a least two parallel-loaded helical tension springs that are arranged coaxially one within the other, and that are wound in opposite directions. The inner spring has an outside diameter which is smaller than the inside diameter of the outer spring. The oppositely wound coils of the coaxial springs cross each other. The two springs are pushed over a holding element which has a narrower first section for receiving the inner spring, and having a wider second section spaced from the first section for receiving the outer spring. The first and second sections of the holding element have edges with hook-shaped portions for grasping coils of the coaxial springs.

BACKGROUND OF THE INVENTION

The present invention concerns a door that can be opened and closed byraising and lowering it vertically, that can be installed against aceiling and slide up and down on rollers, or that can be tilted or swungup and down. It features a weight-compensation mechanism attached to itat one end and to a fixed point at the other and including one or morehelical-spring modules.

Equipping overhead doors with weight-compensation means to maintain theforces need to open and close them weak is known. Such means include"torsion" springs that apply forces to the door by means of cords andweight-compensation shafts and helical springs, both tension andcompression.

When helical springs are involved, means of preventing broken sectionsfrom flinging out are necessary. Such means can be tubes that telescopein the event of breakage and devices that extend within the spring andintercept the fragments.

The diameter of the tubes must be longer, the longer the diameter of thespring, which depends in turn on its performance curve in that springsintended to accommodate more powerful forces must be wider than thoseintended to accommodate weaker ones.

Several weak helical tension springs have been paralleled as analternative to a single more powerful spring. In this approach, however,each individual spring must be provided with a safety-ensuring device ofits own extending through it.

The advantage of several parallel springs is that, if a spring breaks,the forces acting on the door will not all be eliminated. Still, amodule comprising several springs of specific power or storage capacitywill occupy considerable space.

SUMMARY OF THE INVENTION

The present invention is intended to reduce the space needed toaccommodate such helical-spring modules.

This object is attained in accordance with the present invention in thatthe helical-spring module or modules includes or include at least twoparallel-loaded coaxial or nested helical springs, whereby the outsidediameter of the coil of the inner spring is shorter than the insidediameter of the coil of the outer spring and whereby the coil of one ofthe springs in a module winds to the left and the coil in the otherwinds to the right, the two coils crossing each other.

The coaxial arrangement of the two or more springs allows an overallperformance curve with a high storage capacity, even in comparison withthose of similar larger and more powerful spring or of several adjacentweaker springs, in little space. The mutual proximity of the coaxial ornested springs is particular important and is possible only because ofthe opposed winding with the coil of one spring crossing that of theother. The springs can accordingly be very close to each other withoutthe coil of one spring engaging the gaps between the coil in the otherspring and jamming it.

Each inner spring intercepts any fragments broken off the outer springand each outer spring constitutes a cylinder surrounding the innerspring, preventing such fragments from flinging out.

When such coaxial tension springs of different diameter are mountedhorizontal, they will also prevent each other from sagging. Compressionsprings on the other hand will help to prevent each other from bucklinghorizontally, and this function can be augmented with a guide in theform of a tube surrounding them or of a rod extending through them.

The surfaces of the coils that come into contact are protected fromfriction in one preferred embodiment by a slick intermediate layer,preferably a sleeve of low-friction plastic.

When helical compression springs are employed, they are conventionallysecured at the ends. When helical tension springs are employed, theircoils can basically be provided with hooks at their ends at an angle totheir winding. One preferred embodiment also employs flat-ended helicaltension springs thrust over accommodations as disclosed in Europe Patent0 266 061 B1 and German 3 924 947 C2.

Tension-spring modules of the type illustrated herein at one end of aspring are employed with ceiling-mounted doors paralleling thehorizontal sections of track and especially at the outer sides. The endsof the springs remote from the door can be fixed and the other endsprovided with pulleys secured in bearings comprising cheeks 35 and 36.The pulleys in turn accommodate the cords that transmit to the door theforces exerted by the springs. Additional security is provided by usingtwo parallel cords that extend around grooves in the circumference ofthe pulleys and into adjacent holders at their ends. The cords can besecured to the track at one end by rockers to distribute the load toboth cords equally.

A force-per-extent performance curve that is staggered over both theexpansion and compression sections can be achieved if, instead ofactuating all the springs at once, one spring is secured throughappropriate distancing of its engagement or support while thehelical-spring module is unloaded or relieved and engages only duringextension or compression of the module subsequent to a certain initialdistance.

BRIEF DESCRIPTION OF THE DRAWINGS

Preferred embodiments of the present invention are recited in thesubsidiary claims and will now be specified with reference to theaccompanying drawing, wherein

FIG. 1 is a perspective view of the back of a ceiling-mounted door alongwith its tracks, the weight-compensation mechanism being incompletelyillustrated,

FIGS. 2a and 2b comprises side view embodiments as seen from the doorand a top view of the horizontal and sloping and curved sections oftrack,

FIGS. 3a to 3e illustrate various versions of one or more parallelspring modules, each comprising two coaxial springs, along with aschematic details of the springs.

FIGS. 4a and 4b comprise respectively a larger-scale detail of part ofthe embodiments illustrated in FIG. 3c and a partly sectional top viewthereof,

FIGS. 5a to 5f comprise larger-scale perspective views of variouscomponents of the mechanisms illustrated in FIG. 1,

FIG. 6 is a schematic side view of a one-piece tilting door with aweight-compensation mechanism in the form of helical compression-springmodules on each side, and

FIGS. 7a and 7c illustrate embodiments of helical-spring modulescomprising compression springs.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The ceiling-mounted door schematic illustrated in FIG. 1 is composed ofa series of panels 10. The panel 10' that is uppermost and the panel 10"that is lowermost when the door is closed differ from the rest of thepanels. Aside from uppermost door panel 10', all the panels areconventionally supported by rollers 11 that travel in a set of tracks ateach edge of the door. Each track comprises a horizontal section 12, acurved section 12', and a vertical section 12". Uppermost door panel 10'is supported at its upper edge 13 by rollers 11 that travel in anotherset of tracks at each side of the door. The tracks in the second setcomprises a horizontal section 14, a section 14' that slopes down towardthe doorway, and a bent-down section 14".

Such an embodiment is in-itself known. The illustrated door is providedwith an in-itself basically known weight-compensation mechanism 15comprising helical tension springs and associated cords. In thisparticular embodiment, a single spring parallels each horizontal sectionof track. The spring is secured to the wall of the building and, towardthe door, to a deflection pulley. A cord extends around each pulley andis attached at one end to the lower edge of the uppermost panel and atthe other to a fixed point, specifically to a component of the doorcase.The illustrated embodiment has a tension-spring system against eachoutward-facing side of horizontal sections 12 and 14, and accordinglyoccupies practically no space above or below the tracks. Very littlespace is occupied at each side because the helical tension-springsystems comprise several parallel helical-spring modules 16, the numberdepending on how heavy the door is and on the risk of breakage. Eachspring module in turn comprises two coaxial or nested individual helicaltension springs, with the coils of inner spring 17 winding oppositethose of its associated outer spring 18 and along the same axis. Viewedat a right angle to that axis accordingly, the coils of each springcross those of the other spring at an acute angle, as will beparticularly evident from FIGS. 3a to 3c and 4a and 4b.

Each helical-spring mechanism, comprising one or more parallelhelical-spring modules 16 per horizontal track section, is, as will beevident from FIGS. 5a to 5f, fastened to the wall of the building,specifically at the end of horizontal sections 12 and 14 remote from thedoorway. Where they join each other at the doorway, the sections areprovided with a pair of deflection pulleys 25 or with a singledeflection pulley 25 with two parallel grooves around it. Cords 21 wraparound each pulley and, extending parallel to each other, are secured atthe ends to practically similar structures, specifically to a commonin-itself known stationary attachment 22 at the lower edge 23 oflowermost door panel 10" and at the end nearer the doorway of horizontalsections 12 and 14. The cords wrap around a direction-reversing pulley24 between deflection pulleys 25 and stationary attachment 22 to matchthe change in position of the stationary attachment as the door moves tothe stationary axis of the spring modules.

FIGS. 2a and 2b schematically illustrate how helical-spring modules 16relate to the horizontal sections 12 and 14 of track. An edge-on view isschematically interposed at the middle of the side view in FIG. 2a. Itwill be evident that each spring module comprises two coaxial helicalsprings with oppositely winding coils. The figure also illustrates howthe two parallel cords associated with each spring mechanism aredistributed. Particularly evident is the structure and relative positionof horizontal section 14 and weight-compensation mechanism 15.Weight-compensation mechanism 15 comprises two helical-spring modules16, one above the other. The edge-on view is a section through the twotracks. The side views in FIGS. 2a and 2b illustrate a row 40 of holespunched out of the end of the horizontal section 14 of the second set oftracks extending into the building. These holes are engaged by anchors37 attached to the ends of helical-spring modules 16 that extend intothe building as will be specified hereinafter with reference to FIGS. 5ato 5f.

FIGS. 3a to 3c are "exploded" views of three versions of thehelical-spring mechanisms attached to the sides of horizontal sections12 and 14. The first version (FIG. 3a) includes a single spring module16, the second (FIG. 3b) two, and the third (FIG. 3c) three parallelmodules 16. Each module comprises two coaxial springs 17 and 18,represented abbreviated at the middle. At the ends of each module areconnectors 30, associated with pulley bearings 35 & 36 and anchors 37.Anchors 37 are provided with tabs 38 and 39, one for each tongue 31,31', and 31" in a spring module 16. Below the side views is a top view.How the springs in each spring module are attached will be specifiedhereinafter with reference to FIGS. 4a and 4b.

Illustrated in FIG. 3e is part of a spring module comprising two coaxialsprings, specifically an inner spring 17 enclosed within an outer spring18. The coils 20 of inner spring 17 wind along the springs' axis 29opposite those of outer spring 18 and accordingly cross them at an acuteangle. The outside diameter Da of inner spring 17 is shorter than theinside diameter of outer spring 18. The springs can accordingly moveindependently of one another without the windings of one coming betweenthose of the other, even though the difference between diameters Di andDa is small. Material can be inserted between the springs to decreasefriction between the proximate surfaces of coils 20. Each individualcoil wire can for example be accommodated in a U-shaped sleeve or thecoil as a whole in a cylindrical sleeve of low-friction plastic.

FIGS. 4a and 4b illustrate how the end with the pair of deflectionpulleys 25 of a helical tension-spring system comprising threehelical-spring modules 16 is attached to the springs by a flat overallconnector 30. Connector 30 is provided with three tongues 31, 31', 31"that project out toward the spring modules. The tongues are all in thesame plane, and each comprises a narrower section 32 at the end and awider section 33 between the narrower section and connector 30. As willbe evident from both the side view and the top view in FIG. 4, the outerspring 18 in every helical-spring module 16, the spring with the longerdiameter, is thrust over a wider section 33 and toward connector 30until barbs 34 on the edge 47 of that section engage the coil at thefacing end 19 of the spring, maintaining the tongue inside the spring.Inner spring 17, the spring with the shorter diameter, is similarlysecured by the barbs associated with narrower section 32. The barbs 34and depressions 48 along the opposite edges of narrower section 32 andwider section 33 are displaced along the lengths of the sections to fitthe opposing windings of springs 17 and 18.

At the end of connector 30 facing away from tongues 31, 31' and 31" is apair of cord-deflection pulleys 25 accommodated in a bearing comprisingtwo cheeks 35 and 36. Cheek 35 is in one piece with connector 30 andcheek 36 fastened thereto by a hollow rivet that also comprises the axisof rotation for pulleys 25.

FIGS. 5a to 5f are a series of larger-scale perspective views of detailsof FIG. 1. FIGS. 5a to 5f illustrate how a helical tension-spring systemcomprising one helical-spring module 16 or a stack of parallelhelical-spring modules 16 but represented schematically by a singlespring can be fastened at various points to the wall of the building bythe anchor 37 illustrated in FIGS. 3a to 3e. Anchor 37 is inserted inone of the holes in a row 40 punched out of the horizontal section 14 ofthe second set of tracks. Anchor 37 can be manipulated by finger grips46. A tab 39 extending at an angle to the springs engages the other sideof the section subject to the tension exerted by the springs. Anothertab 38 extending opposite tab 39 is provided with a bore that arrives inalignment with the punched-out hole once tab 30 is in place. A bolt isthen inserted-through the hole and through the bore to secure theassembly as illustrated in FIGS. 5a, 5b, and 5c.

FIG. 5d illustrates how the two parallel cords 21 associated with eachedge of the door are secured at the doorway. Each cord 21 has a thickerend 44 accommodated, preferably like that of a Bowden cable, in asuspension structure 43 and secured there by the force exerted by thespring module on its associated deflection pulley 25. Each suspensionstructure 43 is mounted on a rocker 41 that pivots around an axis 42 tocompensate for the difference in the lengths of the cords and distributethe loads equally. To augment the compensation, the suspensionstructures 43 on each side of axis 42 are farther from deflectionpulleys 25 than the axis itself. Rocker 41 can be inserted in anyopening in a row 45 extending along horizontal section 14 to vary thelength of the stationary assembly, which can accordingly be adapted tothe forces of the particular spring forces, to the lengths of the cords,and to age-dictated changes thereof.

FIG. 5e illustrates how the looped other ends of cords 21 are fastenedto an attachment 22 at the lower edge 23 of lowermost door panel 10".FIG. 5f illustrates a direction-reversing pulley 24 mounted on the sideof the horizontal section 14 or of the sloping section 14' of the secondset of tracks facing the wall of the building.

FIG. 6 is a side view from the inside of a system for manipulating adoor 60 supported on rollers 61 traveling in vertical tracks 63, at theedges of the doorway and displaced by a pair of tie rods 64 articulatedat one end to points 65 more or less halfway up the edge of the door andat the other end to points 66 at the top of tracks 63. Each tie rod 64is engaged by a helical compression-spring module 50 secured at one endto a point 67 of articulation approximately halfway up track 63 and atthe other at a point 68 of articulation at the section of tie rods 64remote from the stationary attachment. When door 60 is closed, rollers61 travel down along tracks 63, shortening compression-spring modules 50and compressing their springs 51 and 52.

FIGS. 7a to 7c are a series of lateral sections through the helicalcompression-spring module 50 illustrated in FIG. 6. Its inner spring 51is coaxial with its outer spring 52 at enough of a gap to allow the twosprings to move independently of each other, meaning that the outsidediameter Da of inner spring 51 is somewhat shorter than the insidediameter Di of outer spring 52, as will be particular evident from FIG.7c. The springs can be supported on the supports 55 illustrated on theright in FIGS. 7a and 7c. The support 55 in FIG. 7a is constituted bythe base 54 of a telescoping tube 53.

The ends of springs 51 and 52 and the end of the inner section of thetelescoping tube on the left in FIG. 7a are illustrated broken. Theouter section of the tube is illustrated abbreviated and only partly insection. Springs 51 and 52 can move relative to one another as the tubeis compressed and extended, the opposed winding of their coilspreventing them from interfering with each other. Telescoping tube 53correctly orients the resulting module 50 for operation.

A one-piece tube can be employed instead of a telescoping tube. Such atube is provided with longitudinal slots accommodating a support for theright ends of springs 51 and 52, allowing the tube to slide out over theright-end support to the extent of the length of the slot when thesprings are compressed.

FIG. 7b illustrates another version of a helical compression-springmodule 50 with springs 51 and 52, whereby a hollow guide rod 57 extendsthrough inner spring 51 with its left-hand end attached to a support 55and its right-hand end sliding into and out of a bore in another support56. When the two supports compress the module, the right-hand end of rod57 will emerge part-way out of the bore. The emerging section of guiderod 57 can be protected by an unillustrated cap.

List of Parts

10: regular door panel

10': uppermost door panel

10": lowermost door panel

11: roller

12: horizontal section, first set of tracks

12': curved section, first set of tracks

12": vertical section, first set of tracks

13: upper edge of uppermost panel

14: horizontal section, second set of tracks

14': sloping section, second set of tracks

14": bent-down section, second set of tracks

15: weight-compensation mechanism

16: helical-spring module

17: inner spring

18: outer spring

19: spring end

20: coil

21: cord

22: cord attachment

23: lower edge of uppermost panel

24: direction-reversing pulley

25: cord-deflection pulley

26: stationary cord holder

27: sides of horizontal track sections

28: building-wall spring-module attachment

29: spring axis

30: connector

31, 31', 31": tongues

32: narrower tongue section

33: wider tongue section

34: barb

35: pulley bearing cheek

36: pulley-bearing cheek

37: anchor

38: longer tab

39: shorter tab

40: row of holes

41: rocker

42: axis

43: stabilizing or suspension structures

44: thicker cord ends

45: row of openings

46: fingergrip

47: edge

48: depressions

50: helical compression-spring module

51: inner spring

52: outer spring

53: tube

54: base of the telescoping tube

55: support

56: support

57: rod

60: door

61: rollers

63: track

64: tie rods

65: point of articulation

66: point of articulation

67: point of articulation

68: point of articulation

Di: inside coil diameter

Da: outside coil diameter

What is claimed is:
 1. An overhead door arrangement with a door leafmoveable between open and closed positions and installable against aceiling, said door leaf being slidable or pivotable; said arrangementfurther comprising: weight compensation means having one end connectedto said door leaf and another end connected to a fixed point; saidweight compensation means comprising at least one helical spring modulehaving at least two parallel-loaded helical tension springs storing aload through elastic deformation and arranged coaxially one within theother to form an inner spring with coils and an outer spring with coils,said inner spring having a smaller coil outside diameter than the coilinside diameter of said outer spring; one of said coaxial springs havingcoils wound in a first direction and the other of said coaxial springshaving coils wound in a second direction opposite to said firstdirection, said oppositely wound coils of said coaxial springs crossingeach other; a holding element, said two springs being pushed over saidholding element and having at least one common end, said holding elementhaving a narrower first section facing said coaxial springs forreceiving said inner spring, said holding element having also a widersecond section spaced from said first section and farther from saidinner spring for receiving said outer spring; said first section andsaid second section of said holding element have edges and barbs withhook-shaped portions on said edges for grasping coils of said coaxialsprings pushed over said holding element; a common connector support forcarrying as many holding elements as the number of spring modules, saidcoils wound in opposite directions preventing the coils of said innerspring and said outer spring from hooking into one another for reducingspacing between said inner spring and said outer spring.
 2. An overheaddoor as defined in claim 1, wherein said springs have low-friction coilsurfaces.
 3. An overhead door as defined in claim 2, including a plasticcoating on said coils of said springs.
 4. An overhead door as defined inclaim 1, wherein said holding element has a region facing away from saidfirst section and said second section of said holding element in form ofa roller support for a deflection roller.
 5. An overhead door as definedin claim 1, wherein said holding element has a region facing away fromsaid first section and said second section of said holding element inform of an anchor for securing an associated track.
 6. An overhead dooras defined in claim 1, wherein said helical spring module has springsactuated over different expansion lengths.
 7. An overhead doorarrangement with a door leaf moveable between open and closed positionsand installable against a ceiling, said door leaf being slidable orpivotable; said arrangement further comprising: weight compensationmeans having one end connected to said door leaf and another endconnected to a fixed point; said weight compensation means comprising atleast one helical spring module having at least two parallel-loadedhelical tension springs storing a load through elastic deformation andarranged coaxially one within the other to form an inner spring withcoils and an outer spring with coils, said inner spring hav ing asmaller coil outside diameter than the coil inside diameter of saidouter spring; one of said coaxial springs having coils wound in a firstdirection and the other of said coaxial springs having coils wound in asecond direction opposite to said first direction, said oppositely woundcoils of said coaxial springs crossing each other; a holding element,said two springs being pushed over said holding element and having atleast one common end, said holding element having a narrower firstsection facing said coaxial springs for receiving said inner spring,said holding element having also a wider second section spaced from saidfirst section and farther from said inner spring for receiving saidouter spring; said first section and said second section of said holdingelement have edges and barbs with hook-shaped portions on said edges forgrasping coils of said coaxial springs pushed over said holding element;a common connector support for carrying as many holding elements as thenumber of spring modules, said coils wound in opposite directionspreventing the coils of said inner spring and said outer spring fromhooking into one another for reducing spacing between said inner springand said outer spring; said springs having low-friction coil surfaces; aplastic coating on said coils of said springs; said holding elementhaving a region facing away from said first section and said secondsection of said holding element in form of a roller support for adeflection roller; said helical spring module having springs actuatedover different expansion lengths.
 8. An overhead door arrangement with adoor leaf moveable between open and closed positions and installableagainst a ceiling, said door leaf being slidable or pivotable; saidarrangement further comprising: weight compensation means having one endconnected to said door leaf and another end connected to a fixed point;said weight compensation means comprising at least one helical springmodule having at least two parallel-loaded helical tension springsstoring a load through elastic deformation and arranged coaxially onewithin the other to form an inner spring with coils and an outer springwith coils, said inner spring having a smaller coil outside diameterthan the coil inside diameter of said outer spring; one of said coaxialsprings having coils wound in a first direction and the other of saidcoaxial springs having coils wound in a second direction opposite tosaid first direction, said oppositely wound coils of said coaxialsprings crossing each other; a holding element, said two springs beingpushed over said holding element and having at least one common end,said holding element having a narrower first section facing said coaxialsprings for receiving said inner spring, said holding element havingalso a wider second section spaced from said first section and fartherfrom said inner spring for receiving said outer spring; said firstsection and said second section of said holding element have edges andbarbs with hook-shaped portions on said edges for grasping coils of saidcoaxial springs pushed over said holding element; a common connectorsupport for carrying as many holding elements as the number of springmodules, said coils wound in opposite directions preventing the coils ofsaid inner spring and said outer spring from hooking into one anotherfor reducing spacing between said inner spring and said outer spring;connector means facing away from tongues at one end of said springs;cheeks on said connector means and comprising a bearing for deflectionpulleys; said connector means having an anchor for attachment to anassociated track section.